Aon Center tallest 'green' building in nation

A downtown high-rise has won a distinguished honor for saving energy. Household appliances are Energy Star Rated- and so are buildings. Chicago is one of the top five cities with the most Energy Star Rated buildings in the country. And the tallest.

The Aon Center has won the honor of being the tallest Energy Star Rated building in the nation. It's storefront in the pedway shows off the green initiatives. It was one of 134 buildings that recently helped Chicago move from number 6 to number 5 on the EPA's annual list of cities with the most Energy Star buildings.

TOP 5 CITIES WITH ENERGY STAR BUILDINGS:

1. Los Angeles

2. Washington

3. San Francisco

4. Denver, CO

5. Chicago, IL

"Initially, it was a benchmarking tool that we could use to compare ourselves and since then it has become a corporate initiative at Jones Lang LaSalle. So all of their buildings actually go towards Energy Star," said Mike Lyons, operations manager, Jones Lang LaSalle.

Variable speed drives are among the upgrades that helped the Aon Center earn its seal. The system was running at 27- percent while ABC7 was there.

"So you're getting a 63% savings on your energy use right now."

That equipment controls the fans. Before this technology, they ran at full blast -- all of the time.

"With savings of over 21% in energy costs and up to $550,000 since the inception," said Lyons.

The company's commitment to saving energy is also why it is shutting off its crown lights and all non-safety exterior lights during earth hour. ComEd says it saw as significant reduction in energy use by those who participated last year.

"That represented about more than 150,000 pounds of carbon dioxide not released into the atmosphere or it would be the equivalent of planting 19 acres of trees to get the same sort of carbon dioxide reduction," said Jeff Burdick, ComEd.

Earth Hour is a global campaign of World Wildlife Fund. On Saturday night from 8:30 to 9:30, you are encouraged to turn off the non-safety lights in your home.